1. Field of the Invention
The Parent inventions relate to the technical field of wireless communication devices and, in particular, to techniques for measuring, recording, storing, retrieving, and displaying signal strengths and other parameters as a function of location along paths. This C.I.P. teaches critical improvements that increase a mobile device's battery life while recording signal strength and other parameter data, uses a sensitivity calibration method to solve the problem of differences in signal sensitivities between device models, and enables efficient sharing of map-based signal strength and other parameter path data to internet-based cloud storage platforms.
2. Description of Related Art
It is well known in the art that cellular wireless systems rely on base stations that cover a limited geographic area, and that a cellular telephone needs to be within the reach of a base station to be able to place, receive or conduct a call. Coverage in any cellular system is not universal, and mobile devices are well-known to have an ability to display signal strength.
In some circumstances signal strength may be a life-or-death matter. There are many instances where a person or persons have gotten lost in an area with poor or no cellular coverage, and has died as a result of not being able to call for help.
There exist databases of cellular signal strength as a function of location, but these data are unavailable when a user needs them the most, that is, when the user is already in a location with no useable cellular signal. Additionally, existing databases are designed to allow a user in a fixed location to choose an optimal service provider and show zones of predicted signal strength based on measurement and interpolation rather than showing exact locations with measured data. These existing databases also require the user to be in an area where there is at least some signal in order to compare signals between available networks in order to pick the best choice of service provider. These databases also do not allow users to display or select data based on the path taken during data measurement—a user standing in one location without a phone signal who wishes to move toward the nearest location with a useable phone signal is not provided with a navigable path between those locations. Traveling directly toward the desired location may cause the user to encounter dangerous, impassable obstacles like rivers, roads, mountains, or landmines.
When a mobile device user has poor or no cellular coverage, there is no way for said user to know where a useable cellular signal might be found. For example, thousands of people die every year while lost in the wilderness, but if they were able to place phone calls for help they could be rescued. Many of those people are within walking distance of a useable cellular signal but have no way of knowing whether it exists or where to find it. All existing web-based signal strength databases provide no information when users need it most, i.e., when they have no cellular coverage.
A solution to this technical problem that would provide signal strength and location information to users in a no-coverage location, allowing them to follow an established navigable path to find a useable cellular signal would thus be of great value. Several advantages of one or more aspects are to provide a map of cellular signal strength data as a function of location that is available to a mobile device user even when said device is unable to access the internet. The Parent application Ser. No. 14/273,472 teaches the recording, displaying, and sharing of signal strength data along a path. There is no standardization between mobile device manufacturers to address the different sensitivities of mobile devices. The signal strength threshold for making a phone call on one model of mobile device may be −101 dBm and on another mobile device it may be −114 dBm. This C.I.P. teaches methods of calibration to correct for differences in sensitivities between different devices.
A mobile device's display consumes a significant percentage of the total power used by the mobile device and therefore limits the time the mobile device can be powered on before requiring a recharge. This C.I.P. teaches a solution for extending the mobile device's battery life while collecting path-based parameter data by allowing the recording of data in the background, when screen is turned off completely while the application is still running. Another mode of the application allows the display screen to be dimmed between recording each data point, brightening as each data point is collected to show the result to the user. While the application is running in either the screen-off background mode or the dimmed screen mode, the application can play audio cues on the phone to communicate information about the collected data, with different sounds representing different thresholds of signal strength, distance from a navigable path, or other parameters.
These and other advantages of one or more aspects will become apparent from a consideration of the ensuing description and accompanying drawings.